<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>vue</title>
  <!-- 1.引入vue.js框架 -->
  <script src="./js/vue.js"></script>
</head>

<body>
  <!-- 2.挂载点 -->
  <div id="app">

    <h3>{{title}}</h3>
    <!-- 使用此指令，对于数据只会绑定一次，后续数据的改变，它不会进行重新渲染 -->
    <h3 v-once>{{title}}</h3>

  </div>

  <script>
    const vm = new Vue({
      el: '#app',
      data: {
        title: '上完今天还有4天'
      }
    })
  </script>

</body>

</html>